In recent years, an organic EL display device of a self light emitting type using an organic electroluminescence (EL) element has attracted attention as a display device that can replace a liquid crystal display device. Here, a typical organic EL display device includes a sealing film provided to cover an organic EL element in order to suppress degradation of the organic EL element due to incorporation of, for example, moisture and oxygen.
For example, PTL 1 discloses a method for producing an organic EL element. In the method, a sealing film is patterned by performing dry etching with use of a metal mask to remove a portion of the sealing film.